Engine starter



May 21 1940 o. F. GQTTLIEB ETAL 2,201,310

ENGINE STARTER Fiied March 31, 1939 2 sheets-sheet 1 JMJ/enfans 75552" F. @Uff/25]: v TF5 M/ZDn dimes May 21, 1940 o. F. GQTTUEB ET AL 2,201,310 n ENGINE STARTER Filed Mayen 5 1, 1959 @sheets-sheet 2 .Ajrll "21.

Patented May 21, 1940 RISSUED JAN 13 1942 2,201,310

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OFFICE ENGINE STAR-TER Oscar F. Gottlieb, Milwaukee, Ira Milton Jones,

Thiensville, and Erich Eugene Kohls, Milwaukee, Wis., assignors to Briggs & Stratton Corporation, Milwaukee, Wis., a corporation of Delaware Application March 31, 1939, Serial No. 265,252

19 Claims.

This invention relates to engine starters, and has as one of its objects to provide a more compact and efficient starter mechanism for use in automobiles.

Another o bject of this invention is to provide an engine starter in which the pinion stop which limits motion of the pinion toward its operative position is entirely independent of the drive shaft so as to obviate the necessary for mounting a separate stop collar on the shaft.v

Another object of this invention is to provide a structure in which the pinion stop engages an external portion of the pinion or a part carried thereby so as to permit the smallest possible overall diameter for the pinion and its directly associated parts, to thereby adapt the starter for use With small engines where space is limited.

Another object of this invention is to provide an engine starter of the type in which resiliency in the drive from the shaft to the pinion is obtained through the use of a rubber driving element held in compression and effecting its driving function through frictional contact with adjacent surfaces, wherein adequate means are i provided for precluding the passage of oil and dirt to the rubber element, and wherein `this same means is utilized to limit the motion of the pinion to operative position.

Another object of this invention is to provide an engine starter of the type described wherein all of the operating mechanism is housed within an outer barrel-like shell which guards the threaded portions against coming in contact with dirt and foreign matter, and generally improves the operation of the starter and enhances its appearance.

With the above and other objects in. view which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described. and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the herein disclosed invention may be made as come within the scope of the claims. The accompanying drawings illustrate one complete example of the physical embodiment of the invention constructed in accordance with the best mode so far devised for the practical application of the principles thereof, and in which:

Figure 1 is a longitudinal section view through an engine starter constructed in accordance with this invention, with the parts shown in the positions they occupy when the pinion is retracted;

Figure 2 is a view similar to Figure 1, showing the parts in the positions they assume when the pinion teeth abut those of the ring gear;

Figure 3 is a view similar to Figure 1, showing the pinion fully meshed with the ring gear an about to transmit rotation thereto;

Figure 4 is a cross sectional View through Figure 3 on the plane of the line 4 4; and

Figure 5 is a perspective view of the outer shell per se.

Referring now particularly tothe accompanying drawings in which like numerals indicate like parts, the numeral 5 designates an engine ring gear with which a pinion 6 is adapted to be meshed. The pinion 6 is mounted to move longitudinally along the drive shaft I of a starting motor 8 and to turn therewith, as is customary.

The pinion is propelled to and from its operative position meshing with the ring gear, as shown in Figure 3, by means of a driving member 9 loosely slidable on the shaft and having a threaded connection with the pinion. This threaded connection is formed by external threads I0 on the driving member engaging internal threads IIv in the bore of a hub I2 extending rearwardly from the pinion proper. The hub may be an integral part of the pinion or it may be formed separately and brazed or otherwise secured thereto.

Rotation is imparted to the driving member from the shaft through a resilient driving connection comprising a collar I3 of rubber or other suitable material having cubical elasticity and having a high coefficient of friction, confined between one face of a ange I4 on the driving member and one face of a ange I5 which forms part of a collar IB. The collar I6 is mounted o`n the shaft and secured thereto by a set screw I1.

The anges I4 and I5 are held against separation beyond a predetermined distance at which the rubber collar is maintained under an initial degree of compression, by means of an outer barrel-like shell or housing member I8. This barrel-like shell is preferably formed from a metal tube and has one end secured to the flange I5 by means of radial outwardly projecting lugs I9 on the periphery of the flange engaging in correspondingly positioned slots 20 in the edge of the shell where they are hel'd by a spring snap ringr 2| engaging in a groove 22 in the inner wall of the shell. curing the adjacent end of the shell to the ange I5 may be employed, as will be readily apparent.

Medially of its ends, the shell is abruptly reduced in diameter to provide a shoulder 23 with Any other suitable manner of Sel0 which the flange I4 is engageable to limit movement thereof away from the flange I5. In this manner, the anges I4 and I5 are held against separation beyond a predetermined distance to at all times maintainthe rubber collar I3 under an initial degree of compression to insure the transmission of rotation from the drive shaft to the driving member,

As is well known, upon initial rotation being imparted to the driving member, the pinion, bey cause of its inertia, does not turn, but is propelled longitudinally toward the ring gear 5. If during its forward propulsion, it strikes the teeth of the ring gear, the endwise resiliency of the rubber collar cushions the impact and builds up sufcient torque to turn the pinion and eifectproper meshing.

When the pinion reaches its fully meshed position, its forward propulsion should cease so that the load of the engine can be picked up. I-Ieretofore, the stop to limit forward motion of the pinion was generally a separate collar secured to the shaft inwardly of the ring gear to be engaged by the end of the pinion as it moved to its fully meshed position. This construction has obvious objections, which are entirely overcome with the present invention.

In this instance, the forward propulsion of the pinion is limited by the engagement of a collar 24 threaded, welded or otherwise secured to the end of the pinion hub I2 in position to'- engage an inturned flange 25 on the adjacent end of the outer shell. only holds the anges I4 and I5 against separation to maintain the rubber ring in compression, but also provides the pinion stop, and because it engages the pinion externally, it follows that the diameter of the pinion may be held to a minimum compatible with good design.

Inasmuch as the collar 24 and the flange 25 move relative to each other as the load of the engine is picked up and the rubber ring twists, a hardened washer 25 is provided therebetween.

The outer shell-like housing has the additional function of excluding oil and extraneous matter from the rubber ring and the screw threads, even when the pinion is projected to its operative position shown in Figure 3. In other Words, the entire driving mechanism for propelling and driving the pinion is housed within the `outer shell.

An additional safeguard against ingress of oil and foreign matter into the interior of the shell is provided by a sealing ring 26 retained ina groove 21 formed in the outer surface of the.

collar 24 and slidably engaging the adjacent inner cylindrical surface of the shell.

Accidental or unintentional meshing of the pinion with the ring gear is prevented by a light anti-creep or rebound spring 28 confined between the flange 25 on the shell and a shoulder!!! `on the collar 2d formed by having its outer surface stepped.

From the foregoing description taken in connection with the accompanying drawings, it will be readily apparent that this invention provides an engine starter which is exceptionally compact and which, because itsiouter protecting housing completely conceals all of the driving mechanism, not only guards against ingress of dirt, oil and grease and other extraneous matter into the interior ofthe unit, but also has improved appearance.

What we claim as our invention is:

1. In an engine starter, the combination of: a

The outer barrel-like shell thus not driving shaft; a pinion movable along the shaft to and from engagement with an engine member; a sleeve on the pinion; a member having a screw connection with the pinion sleeve and operable upon rotation with the shaft to propel the pinion toward its operative position; an endwise and torsionally resilient driving connection between said member and the shaft; and means encircling said member and the driving connection and engageable with a part on the pinion sleeve to limit motion of the pinion toward operative position.

2. In an engine starter, the combination of a. drive shaft; an engine driving unit movable along the drive shaft, said engine driving unit including a pinion; means operable upon relative rotation between the shaft and the engine driving unit for propelling the engine driving unit along the shaft, said means including, an endwise and torsionally resilient driving connection; and means encircling the driving connection and engageable with a portion of the engine driving unit to limit movement thereof toward operative position.

3. In an engine starter, the combination of a drive shaft; a drive member including a pinion and movable along the shaft to and from an operative position engaging an engine member; .an i actuating member loose on the shaft and havingr a threaded connection with the drive member whereby relative rotation between the drive member and said actuating member effects endwise ymovement of one with respect to the` other; a

resilient driving connection from the shaft to said actuating member; and means covering the driving connection and the threaded connection and having a portion engageable with the drive member to limit movement of the drive member and define its operative position.

4. An engine starter of the character described comprising: a barrel-like outer shell; a pinion; a tubular extension on the pinion projecting into one end of the shell; cooperating means on the shell and said tubular extension 'engageable to limit endwise motion of the tubular member out of the shell; a member xed to the opposite end of the shell and bored for reception of a drive shaft to which said member is securable so that the shell becomes xed with respect to the drive shaft, said shell and the tubular pinion extension cooperating to form an enclosure; and a driving connection from said member to the pinion wholly inside said enclosure for projecting the pinion into engagement with the flywheel of an engine to be started and for rotating the pinion after said engagement.

5. In an engine starter, the combination of: a drive shaft; a drive memberincluding a pinion and movable axially along the drive shaft and rotatable therewith; a driving connection from the shaft to the drivemember operable to auto-y matically propel the drive member toward its operative position upon initial rotation of the drive shaft, said driving connection having endishaft and rotatable therewith; a member loose g5 on the shaft and having an external thread; a sleeve on the pinion internally threaded and engaging the external thread of said member; a driving connection from the shaft to said member; and means for limiting endwise forward movement of the pinion toward one end of the shaft, said means comprising a shoulder on Athe exterior of the sleeve, a part supported from the opposite end portion of the shaft and directed forwardly towards the pinion, and an abutment on said part engageable with the shoulder on the sleeve.

7. In an engine starter, the combination of: a drive shaft; a pinion movable endwise along the shaft and rotatable therewith; a sleeve on the pinion larger in diameter than the pinion and provided with an internal screw thread; a member loose on the shaft and externally threaded to t the threads of the pinion sleeve; a

driving connection from the shaft to said member whereby rotation is imparted from the shaft to the member to automatically propel the pinion toward its operative position and thereafter transmit rotation thereto, said driving connection lying between the pinion and one end of the shaft; and means for limiting endwise movement of the pinion toward its operative position comprising, a member anchored to said end of the shaft and reaching around the driving connection to have a part thereof adjacent to said sleeve, an abutment on said part, and a shoulder on the exterior of the pinion sleeve engageable with said abutment.

8. In an engine starter including: a pinion; an internally threaded sleeve on the pinion; a member having an externally threaded portion threaded in said pinion sleeve; a member adapted to be secured to a drive shaft; a resilient driving connection between said members including, a rubber element drivingly connected with said members solely through frictional engagement; means enclosing said connection to exclude grease and dirt therefrom; and cooperating means on said last named means and the pinion sleeve for limiting endwise movement of the pinionv in one direction.

9. An engine starter of the character described comprising: a pinion; a threaded sleeve on the pinion; a driving member having a threaded portion threaded to the pinion sleeve whereby relative rotation between the pinion and said driving member effects` relative endwise motion between said parts; a member adapted to be fixed to a drive shaft; a rubber element confined between said driving member and said last named member to provide a resilient driving connection therebetween; an outer housing receiving support from the member which is attachable to the drive shaft; means on the outer housing engageable with the driving member to limit movement apart between said members and maintain the rubber element in compression; and means carried by said housing member` and engageable with a part on the pinion sleeve to limit endwise movement of the pinion in one direction.

10. An engine starter of the character described comprisingz'a pinion; a threaded sleeve on the pinion connected thereto; a driving member having a threaded portion threaded to the pinion sleeve whereby'relative rotation between the pinion and said driving member effects relative endwise motion between said parts; a member adapted to be fixed to a drive shaft; a rubber element conned between said driving member and said last named member to provide a resilient driving connection therebetween; an outer housing receiving support from the member which is attachable to the drive shaft; means on the outer housing engageable with the driving member to limit movement apart between said membersand maintain the rubber element in compression; an extension on said housing member projecting toward the pinion; and cooperating means ,on said extension and the connected pinion and sleeve engageable to limit endwise movement of the pinion in one direction.

1l. An an engine starter of the character described comprising: a pinion; a threaded sleeve on the pinion; a driving member having a threaded portion threaded to the pinion sleeve whereby relative rotation between the pinion and said driving member effects relative endwise motion between said parts; a member adapted to be xed to a drive shaft; a rubber element conned between said driving member and said last named member to provide a resilient driving connection therebetween; an outer housing receiving support from the member which is attachable to the drive shaft; means on the outer housing engageable with the driving member to limit movement apart between said members and maintain the rubber element in compression; and a pinion stop carried by said housing member.

12. An engine starter of the character described comprising: an outer one-piece barrellike shell having a solid unyielding wall from end to end; an inturned ange at one end of the shell; a pinion; a part connected with the pinion and extending into the flanged end of the shell, said part having an abutment inside the shell for engagement with the flange to limit movement apart between the pinion and shell; a member fixed to the open end of the shell and bored for reception of a drive shaft to which said `member is securable to fix the entire shell including said flange with respect to the drive shaft; and pinion propelling and driving means inside said shell.

13. An engine starter of the character described comprising: a barrel-like outer shell; a pinion; a part extended from the pinion into the shell; co-operating means on said part and the end of the shell nearest the pinion for limiting relative endwise motion thereof apart; a member securable to a drive shaft and connected with the shell; and a torsionally resilient driving connection from said member to the pinion, said driving connection including internal threads on said part extended from the pinion and an externally threaded actuator inside the shell and engaging the internal threads of said pinion part so that the threaded connection is at all times covered.

14. An engine starter'of the character described comprising: a barrel-like outer shell; means providing an abutment at one end of the shell; a pinion; a. part extended from the pinion into said end of the shell; means on said part engageable with the abutment to limit outward movement of the pinion with respect to the shell; a member fixed to the shell and bored for reception of a drive shaft to which said member is securable, whereby the shell becomes fixed with respect to the drive shaft and engagement of the means on the pinion part with the shell abutment constitutes a pinion stop; and a torsionally resilient driving connection from said member to the pinion inside the shell, said driving connection including a resilient element through which the driving force is transmitted.

15. An engine starter of the character described comprising: a barrel-like` outer shell; means at one end of the shell providing an abutment inside the shell; a pinion; an internally threaded part extended from the pinion into the shell; means on said part engageable with the abutment to limit outward movementof the pinion with respect to the shell; a member xed to the shell and bored for reception of a drive shaft to which said member is securable, whereby the shell becomes fixed with respect to the drive shaft and engagement of the means on the pinion part with the shell abutment constitutes a pinion stop; a driving connection from said member to the pinion, said driving con-V nection comprising, a driving member inside the' shell and having an external thread engaging the threads of the pinion part; cooperating means on the driving member and the shell for limiting movement of the driving member away from the rst named member while permitting movement thereof toward said rst named member; and a rubber element confined between said two members and capable of transmitting rotation from one to theother.

16. An engine starter of the character described comprising: an outer barrel-like shell having an instruck flange at one end; a pinion; a sleeve extended from the pinion into said end of the shell; a stop collar secured on the inner end of the sleeve and engageable with the instruck ange to limit outward movement of the pinion with respect to the shell; amember xed to the opposite end of the shell, said member being bored for reception of a drive shaft to which said member is securable; a driving member inside the shell and having a threaded connection with the pinion sleeve; and a resilient driving connection from said bored member to the driving member.

17. An an engine starter of the character described comprising: an outer barrel-like shell having an instruck ange at one end; a pinion;

a sleeve extended from the pinion into said end of the shell; a stop collar secured on the inner end of the sleeve and engageable with the instruck iiange to limit outward movement of the pinion with respect to the shell; a member xed to the opposite end ofthe shell, said member being bored for reception of a drive shaft to which said member is securable; a driving member inside the shell and having a threaded connection with the pinion sleeve; a resilient driving connection fromsaid bored member to the driving member; and an oil seal between the collar on the pinion sleeve and the inner face of the shell to retard the passage of oil and other foreign matter into the interior of the shell.

18. In an engine starter including a shaft and a pinion movable longitudinally thereof and rotatably therewith and drivingv means connected with the shaft and the pinion to effect such motion of the pinion: a pinion stop for limiting longitudinal movement oi' the pinion toward operative position, means for Vsupporting said stop from means carried by the shaft at a point remote from the pinion, said stop supporting means being wholly disposed exteriorlyoi said driving means; and an abutment movable with the pinion and engageable with said stop.

19. In an engine starter including a shaft and a pinion movable longitudinally thereofand rotatably therewith and av driving connection between the shaft and the pinion to eiect such motion of the pinion, said driving connection having torsional and endwise resiliency provided by a rubber drive transmission: a stop for limiting longitudinal movement f the pinion toward operative position; means for supporting the stop from means carried by the shaft at a point remote from the pinion, said stop supporting means being wholly disposed exteriorly of said driving connection and forming a protecting housing therefor; and an abutment movable with the 

